中学生長距離選手のランニングにおけるクリティカル速度の運動強度の指標としての有用性
田中 宏暁 中村 さおり 村上 清英 鬼塚 純一 田中 守 進藤 宗洋
Validity of critical velocity during running exercise as an index of relative exercise intensity in junior high school runners
Hiroaki TANAKA, Saori NAKAMURA, Kiyohide MURAKAMI, Junichi ONIZUKA, Mamoru TANAKA, Munehiro SHlNDO
The linear relationship between exhaustion time (t lim) and distance (D lim) was described for running exercise. The slope of the line of D lim as a function of t lim is defined as critical velocity (CV) , which might be very closely to the maximal speed where blood lactate concentrations are maintained at a steady-state during exercise (MaxLass) . This study investigated the critical velocity determined by the field tests as an index of MaxLass in junior high school boys and girls. Eight long distance runners in junior high school (boys=5, girls=3) participated in the study which compared CV, velocity at 4 mmol/l of blood lactate (4 mmolLA), and MaxLass. The CV was calculated as the slope of the linear line formed for D lim as a function of t lim from the results of 1000m and 2000m time trials performed in random order. Four mmoLA was obtained from the lactate and running velocity relationship determined during incremental running test. MaxLass was identified the maximal running velocity where blood lactate concentrations did not vary by more than 1 mmol/l during the final 4000m during a 10000m run. CV as well as 4 mmolLA was significantly higher than MaxLass. However, the CV was highly correlated to the MaxLass (r=0.954) , although it overestimated Max Lass by less than 10%. This correlation was stronger than that between 4 mmolLA and MaxLass (r=0.934) . It is concluded that this method of determin-ing CV with 1000m and 2000m time trials may useful for estimating MaxLass in junior high school endurance runners.
福岡大学体育学部運動生理学研究室 Laboratory of Exercise Physiology, Department of Physical Educa-tion, Fukuoka University
